Ideas
- Firmware version
- Kernel arguments
- Disable any customization like extensions, widgets, themes …
- Have you any bittorrent clients running?
- Have you tried another browser?
I would expect the freeze to occur no matter the desktop used?
Have you verified by using e.g. LXQt or XFCE - try running from a live system - you can modify GRUB to boot an ISO from your disk.